# ECT122 W2 ILab 3

Topics: Ohm's law, Resistor, Electric current Pages: 6 (954 words) Published: January 21, 2015
﻿ECT 122 Week 2 iLab #3 Part 1
Parts:
DC Power Supply
Hand Held DMM
Wire
56kΩ resistor

1. Given the circuit below, use Ohm’s law to determine the total current in the circuit and the voltage across the resistor.

5V

My mulitsim of this circuit.

2. Construct the circuit above on the breadboard. Starting at the positive terminal of the +5 V power supply, follow the schematic around to install each component.

3. The first component is a wire that will connect the +5 V connection of the power supply to the resistor.

4. Install a 56KΩ resistor.

a. One lead will be connected in the same row as the wire that goes to the power supply positive terminal.

b. The second lead of the 56kΩ resistor can go into any other row of the protoboard.

c. Check to see that the leads are in different rows so that they are not shorted.

5. Coming from the other side of the 56kΩ resistor is a wire going to the GND connection of the power supply. Install this wire so that it is in the same row as the second lead of the resistor. Do not connect the wire to the power supply GND terminal at this time.

6. Have the professor verify the circuit.

7. Apply power to the protoboard, and measure the voltage across the +5 supply using the handheld DMM. Does the handheld DMM read +5 V (YES/NO)? If not, correct the problem and re-check the voltage. Turn off the power to the protoboard.

Yes.

8. Finish connecting the GND connection of the power supply to the protoboard. Check to see that the positive and negative terminals are connected to the correct wires. Apply power.

9. Again, measure and record the voltage at the power supply. ____4.99V______ 10. Measure and record the voltage across the resistor. ____4.99V____

11. Measure and record the current between the positive terminal of the power supply and the resistor. (Note: You must break the circuit and insert the handheld DMM.) __88µA______

12. Measure and record the current between the negative terminal of the power supply and the resistor. ____88µA__________

Create an open circuit by moving the wire connecting the positive terminal of the power supply to another row in the breadboard where the resistor lead is not located.

13. Measure and record the voltage at the power supply. ___4.99V______

14. Measure and record the voltage across the resistor. _____0_______

15. Measure and record the voltage across the open created by moving the wire. (To do this, insert two new wires; one in the row where the wire from the power supply is located and one where the resistor lead is located.) __4.99V______

Repair the open circuit by moving the wire from the positive terminal of the power supply back to its original location. Create a new open between the negative terminal of the power supply and the resistor.

16. Measure and record the voltage at the power supply. __4.99V______

17. Measure and record the voltage across the resistor. _____0_______

18. Measure and record the voltage across the open created by moving the wire. _____4.99V_____

If you are using an ELVIS environment, use the ELVIS DMM to make the following measurements. If you are NOT using an ELVIS environment, skip steps 19–22.

19. Measure and record the voltage at the power supply. ____________ 20. Measure and record the voltage across the resistor. ____________

21. Measure and record the current between the positive terminal of the power supply and the resistor. (Note: You must break the circuit and insert the ELVIS DMM.) ____________ 22. Should the ELVIS DMM measurements agree with the hand held DMM measurements? (YES/NO) Were the measurements in agreement? (YES/NO) If no, determine the problem and repeat the measurement.

Part 2
Circuit Faults and Power
1. What is an open circuit? How much current flows in a circuit with an open circuit? Draw a simple circuit...